中文摘要：

应用乙炔抑制一培养法研究了水分、温度、氮源和碳源等影响因子对三峡库区腹地消落带土壤N2O排放和反硝化作用的影响，并与原位试验结果进行了比较。结果表明，土壤含水量是影响土壤N2O排放和反硝化作用的重要因素，反硝化速率随着土壤充水孔隙度（WFPS）的增加而增大，土壤反硝化速率最大值出现在土壤WFPS为100％时，N2O排放速率最大值出现在土壤WFPS为60％时。温度在10～40℃范围内，土壤N2O排放速率和反硝化速率随着温度的升高而增大，相关性分析表明，土壤N2O排放速率和反硝化速率均与温度呈显著正相关。外加氮源为NO3—N时，反硝化速率随氮源量的增加有减小的趋势，过多的硝态氮抑制反硝化作用；而添加易被微生物利用的葡萄糖作为碳源则会明显提高土壤反硝化速率，当每千克土加入碳源量为240mg时反硝化速率最大。

英文摘要：

Abstract：In order to study the influences of water filled pore space （WFPS）, temperature, the addition of nitrate （NO;-） and carbon source on NzO emission and denitrification in the soil of water-level-fluctuation zone in the Three Gorges Reservoir area, C2 H2 in hibition incubation experiments are applied. Results from experiments in laboratory and in situ field are analyzed. Results show that the WFPS is a main factor determining N20 emission and denitrifieation. Denitrification rate increases while the WFPS increases, and the maximum denitrification rate and the maximum N20 emission rate appear when the WFPS is 100% and 60~, respectively. In addition, while the temperature is between 10 ~C and 40 ~C, the increase of temperature contributes to the increase of the N20 emission and denitrifieation rates. Furthermore, it is found that the N20 emission and denitrification rates are significantly and positively correlated with temperature. The addition of carbon source could increase denitrification performance in soil. However, the addition of nitrate has a negative impact on the denitrification performance, because nitrogen source is not the main factor determining denitrification performance and excessive nitrate could inhibit the denitrification in these experiments. The addition of glucose, which is a carbon source easily be utilized by denitrifying bacteria, could significantly increase the denitrification rate in soil, and the maximum denitrification rate takes place while the carbon content in per kilogram soil is 240 mg.